The Black River Escarpment is a geological feature in Eastern

Wisconsin Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...

. The escarpment runs parallel to and between the

Niagara Escarpment The Niagara Escarpment is a long escarpment, or cuesta, in Canada and the United States that runs predominantly east–west from New York through Ontario, Michigan, Wisconsin, and into Illinois. The escarpment is most famous as the cliff over ...

and the

Magnesian Escarpment The Magnesian escarpment is the most westerly of three prominent escarpments that run north-south in Wisconsin. All three escarpments are formed by the edges of layers of sedimentary rocks. The easternmost and most prominent escarpment is the Ni ...

. The escarpment marks the boundary between bedrock from Lower Magnesian

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

bedrock In geology, bedrock is solid Rock (geology), rock that lies under loose material (regolith) within the crust (geology), crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface mater ...

and earlier Black River limestone. The escarpment emerges from Green Bay, on

Lake Michigan Lake Michigan is one of the five Great Lakes of North America. It is the second-largest of the Great Lakes by volume () and the third-largest by surface area (), after Lake Superior and Lake Huron. To the east, its basin is conjoined with that o ...

. The escarpment's boundaries are not always visible to the untrained eye, but are marked by cliffs in some regions.

References

{{coord, 43, 45, 57, N, 88, 58, 24, W, type:landmark_region:US-WI_scale:1000000, display=title Landforms of Wisconsin Escarpments of the United States